Based on recent funded research in this laboratory, there is evidence that the vagus nerve (Cranial nerve X) can convey sensory responses to vaginocervical stimulation directly into the brain, completely bypassing the spinal cord. The proposed experiments critically test this evidence and test two means by which the responsiveness of the pathway might be intensified. If this pathway proves to exert behavioral (e.g. analgesia) and/or physiological (e.g. neuroendocrine reflex) effects, then it could be of potential clinical significance in rehabilitation of sexual function after spinal cord injury. The following ar e the research questions that the MBRS students on this subproject would address in physiological and behavioral studies in the laboratory rat: 1. Does vaginocervical sensory activity project via the vagus nerve directly to the Nucleus of the Solitary Tract of the medulla oblongata of the brain, bypassing the spinal cord? This question would be addressed using c-fos bypassing the spinal cord? This question would be addressed using c-fos immunocytochemistry. 2. Can the vagus-mediated response to vaginocervical stimulation be intensified by sensory and/or hormonal treatment; Specifically, a. Does repeated vaginocervical stimulation accelerate recovery of function via the vagus nerve after spinal cord injury? b. Does estrogen stimulate recovery of function in this system? 3. Does vaginocervical stimulation release oxytocin from the neural lobe of the pituitary gland via the vagus nerve? The MBRS students on this subproject would be directly involved in the all phases of the research from formulation of the specific experiments to coauthorship of the publications based on it. They would be trained in methodologies of immunocytochemistry, computerized image analysis, animal microsurgery, polygraph and oscilloscope recording of physiological responses, non-invasive blood pressure and heart rate recording, blood sampling for hormone assays, behavioral bioassay, hormonal radioimmunoassay, behavioral observation and recording, and intensive postsurgical care of the rats after spinal cord transection and/or vagus nerve transection.